In the fields of veterinary medicine and animal husbandry it is sometimes desirable to treat animals via periodic administration of various drugs and agents. Where the course of therapy requires multiple or repetitive administration of drugs or agents, the animals must be located, captured, and restrained until the drug or agent is administered. This process is repeated for each subsequent dosage or administration, which can consume a great deal of time and resources, while potentially endangering the animals and the veterinarian or farm worker. In an effort to alleviate this problem, a number of delivery systems for administering beneficial agents to animals have been disclosed. Examples of such devices are disclosed in U.S. Pat. No. 5,196,002 (Mar. 23, 1993) to Hanover et al.; U.S. Pat. No. 5,162,116 (Nov. 10, 1992) to Shepherd; U.S. Pat. No. 4,564,363 (Jan. 14, 1986) to Bagnall et al.; U.S. Pat. No. 4,457,752 (Jul. 3, 1984) to Vadasz; U.S. Pat. No. 4,439,197 (Mar. 27, 1984) to Honda et al.; and U.S. Pat. No. 4,425,117 (Jan. 10, 1984) to Hugemann et al.
While such devices deliver an agent to the body of an animal in which they are placed, the devices collectively possess a number of disadvantageous limitations. For example, the devices generally lack specific controlled release capabilities, are limited to specific applications, are limited to continuous delivery of the contents therein, are large and difficult to place and maintain in specific areas of the body, or are relatively complicated and costly to manufacture and use. Additionally, many of the existing devices are made of or contain parts that are made of metal (e.g., springs within the housing) which can damage tools, such as a saw blade, or the worker during the dissection or slaughter of the animal. Other devices, such as the osmotic device disclosed in U.S. Pat. No. 5,431,919 (Jul. 11, 1995) to Maruyama et al. also possess shortcomings since they depend on the surrounding water found in ruminal fluid of a ruminant to deliver its contents and does not provide delivery at a constant rate.
Therefore, it would be advantageous to provide a compact, easily manufactured, simple and efficient delivery device which may be introduced into the body of an animal for timed, periodic, controlled and/or slow release of drugs or agents into the animal. It would also be advantageous to provide a delivery device which is reliable, contains a high ratio of contents (i.e., drugs or beneficial agents) in relation to the volume of the container or package, and is made of materials that are lightweight and easy to cut. It would be also advantageous to provide a device which is made up of biologically as well as environmentally friendly materials.